Convert Square miles to Hectares
1 square mile is 259 ha. One square mile is exactly 258.998811034 hectares.
One square mile is 258.99881 hectares. To convert square miles to hectares, multiply by 258.99881; to go the other way, divide by 258.99881 or multiply by 0.0038610216. The relation is exact but the figure is not: it is a rounding of a number that does not terminate, and it follows from NIST Office of Weights and Measures. Exactly 640 acres — one section of the US Public Land Survey, the grid the Midwest is drawn on.
Factor checked against the defining standard · How we check
- Square miles × 258.99881
1 * 258.99881258.999 ha
1 square mile in every area unit
| Unit | Value | Exact factor |
|---|---|---|
| square inches | 4,014,489,600 sq in | × 4,014,489,600 |
| square feet | 27,878,400 sq ft | × 27,878,400 |
| square yards | 3,097,600 sq yd | × 3,097,600 |
| acres | 640 ac | × 640 |
| square meters | 2,589,988.11 m² | × 2,589,988.11034 |
| square millimetres | 2,589,988,110,000 mm² | × 2,589,988,110,340 |
| square centimetres | 25,899,881,100 cm² | × 25,899,881,103.4 |
| square kilometres | 2.58998811 km² | × 2.58998811034 |
| square miles (as entered) | 1 mi² | — |
| hectares | 258.998811 ha | × 258.998811034 |
Factors are entered by hand from NIST Office of Weights and Measures rather than derived from a units library, so the ones that terminate are exact rather than rounded.
The same converter answers this pair however it is written: sqmi to ha is how the symbols are typed on a keyboard with no superscript on it.
How do you convert square miles to hectares? The converter and the working
- 1.Take the measurement in square miles.
- 2.Multiply by 258.99881 — that is how many hectares fit in one square mile.
- 3.To go back the other way, divide by 258.99881, or multiply by 0.0038610216.
Worked example: 25 square miles to hectares
- Formula
- mi² × 258.99881 = ha
- Arithmetic
- 25 × 258.99881 = 6,474.97 ha
- Answer
- 25 mi² = 6,474.97 ha
The factor is rounded for display; the figure above is computed from the full value.
Square miles to hectares conversion table
| Square miles | Hectares |
|---|---|
| 1 mi² | 259 ha |
| 2 mi² | 518 ha |
| 3 mi² | 777 ha |
| 4 mi² | 1,036 ha |
| 5 mi² | 1,294.99 ha |
| 6 mi² | 1,553.99 ha |
| 7 mi² | 1,812.99 ha |
| 8 mi² | 2,071.99 ha |
| 9 mi² | 2,330.99 ha |
| 10 mi² | 2,589.99 ha |
| 12 mi² | 3,107.99 ha |
| 15 mi² | 3,884.98 ha |
| 20 mi² | 5,179.98 ha |
| 25 mi² | 6,474.97 ha |
| 50 mi² | 12,949.94 ha |
| 100 mi² | 25,899.88 ha |
| 200 mi² | 51,799.76 ha |
| 300 mi² | 77,699.64 ha |
| 500 mi² | 129,499.41 ha |
| 1000 mi² | 258,998.81 ha |
| 2000 mi² | 517,997.62 ha |
| 5000 mi² | 1,294,994.06 ha |
| 10000 mi² | 2,589,988.11 ha |
What is a square mile?
Exactly 640 acres — one section of the US Public Land Survey, the grid the Midwest is drawn on. 2.59 square kilometres, and the reason a rural address is often "section 12".
What is a hectare?
10,000 square meters, or about 2.471 acres. The metric unit of land area.
How many hectares are in a square mile?
One square mile is 258.99881 hectares. Going the other way, one hectare is 0.0038610216 square miles. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.
Every area unit here
The whole group — 10 units with their symbols and the size of each one in square meters — is on the conversion index, along with every pair it makes. The table above already gives each of them relative to a square mile.
Cite this page
- APA
- Rule Calculator. (2026). Convert Square miles to hectares. Rule Calculator. https://rulecalculators.com/convert/square-mile-to-hectare
- MLA
- "Convert Square miles to hectares." Rule Calculator, August 16, 2026, https://rulecalculators.com/convert/square-mile-to-hectare.
- Chicago
- Rule Calculator. "Convert Square miles to hectares." Rule Calculator. Last reviewed August 16, 2026. https://rulecalculators.com/convert/square-mile-to-hectare.
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Questions people actually ask
- How many hectares are in a square mile?
- 258.99881. 10,000 square meters, or about 2.471 acres. The metric unit of land area.
- How do I convert hectares back to square miles?
- Divide by 258.99881, or multiply by 0.0038610216 — they are the same operation.
Other area conversions
Hectares to square miles — the same conversion the other way.